﻿<p>The <em>IfcPcurve</em> is a curve defined within the parameter space of its reference surface.</p>
<blockquote class="extDef">
NOTE&nbsp; Definition according to ISO/CD 10303-42:1992<br>
A pcurve is a curve which lies on the basis of a surface and is defined in the parameter space of that surface. The basis curve is a curve defined in the two-dimensional parametric space of a reference basis surface. Although it is defined by a curve in two dimensional space, the variables involved are <em>u</em> and <em>v</em>, which occur in the parametric representation of the referenced surface, rather than the <em>x</em>, <em>y</em>, Cartesian coordinates. The basis curve is only defined within the parametric range of the surface.</blockquote>

<blockquote class="note">
NOTE&nbsp; Entity adapted from <strong>pcurve</strong> in ISO 10303-42.
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<blockquote class="history">
HISTORY&nbsp; New entity in IFC4.
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